Machine for grinding valves and analogous objects



J. H. LITTLER Dec. 3, 1929.

MACHINE FOR GRINDING VALVES AND ANALOGOUS OBJECTS Original Filed Jan. 29, 1925 I VNTOR l? NE Y-S Patented Dec. 3, 1929 UNITED STATES PATENT OFFICE JAMEs HENRY Li'rrta i, or Mantras; new Yon-K, ASSIGN'OR nip s. CHENEY '& son, or MANLIUS; NEW YORK, A CORPORATION OF NEW YoRK MACHINE GRINDiNG VALVES AN D ANAL'GGC US OBJECTS ori inal application filed. January 29, 1925, Serial No. 5,603. Divided am this application riled its 13 1926. Serial This invention relates to a portable machine-tor grinding valves andanalo'gous ob- 'ects havin stems-or shanks and refers more particularly to the means for rotatably holding the work in grinding relation to' a rotary gIHlClQI as a div sion of my Patent No.

1 66 5693, April 3 l928. v r I The main object is toi provide means tor firmly holding the work in the rotaryholder in such manner as to reduce to a minimum means for gripping a relatively long portion of the valve stem or analogous work to hold said stem against lateral springing or vibr tion when the valve 1s rotated against the grinder.

Another object is toenable the work-holder to be adjustedangula-rly about the axis of its driving means as may be required for grind ing valves at different angles to their axes.

Other objects and usesrelating to specific parts of the work-holder and supporting means will be brought out in the following description.

In the drawings 7 Figure 1 a front face view of my improved work-holder and adj acent'portions of its supporting case and rotary grinder together with a portion of the driving gear and pinion for transmitting motion from the gear to the woi'lcholder, the pinion being shown in section.

FigureflQ is a sectional View taken in the plane of line 22,Figure 3.

Figure 3 is a sectional View taken in the plane of line 3-3, Figure 1,-except that the parts are reversed.

As illustrated this device comprises a niain supporting frame consisting in this instance of a gear case 1- composed of sections --7- and -8- secured together-end to end by clamping bolts .10- and provided with suitable "bearings for receiving and supportmg a driving shaft 11- to which is secured a'relatively large driving gear 1-{1- within the gear case.

in b earing s in the gear case and pro Vided with a pinion meshing with the .-14-- as shown in my patent referred to for receiving rotary motion therefrom. v

A bracket -23- is adji 'stably secured by bolts 23- and slots 23 tothje outer end face of section -7 o't the frame --1-- and is provided with a split journal bearing 2 1 in which is joulr naled rotary upright shaft --2 5- tangential to thesha ft and is also provided in its lower'end witha gear chalnber and laterally offset bearing '-27-" for receiving resp ec tively a worinrgear amide rotary 29- said bracket and parts carried theirby bei-ng .adjustable abouttheaais or the shaft -29- to permit the work, as '-a 'to be adju sted toward and from the axis of grinders oi di ileront diameters, or as the fiLCB OIf the grinder --18- is worn away.

The worm gemis seem d tdtlie lower reduced end or aie a nghr, shaft -25f, said reduced end being extended downwardly and joiirnaled in a suitable opening in a bushing -29- which itscrewed intothe lower of the gear charm her to forlnan end thrust bearing for the lower end of hub of thegear 28-- and thereby to hold gear and shaft against downward movement relatively to the bracket 523 I The shaft -29 extends horizontally par allel with tliegrinder shaft and to opposite sides ofthe worm gear -28-; and

also across the periphery of the relatively large gear --14 tangentialfto the shaft 2 5,, and is provided with a relatively small pinion meshin ,with said gear to receive rotary motion therefrom and whereby the shaft -29- will be driven at a relatively high rate of speed as compared with that of the shaft The intermediate portion of the shaft -429- is provided witna gear worm or pinion -31-{meshing with the gear 28- for driving the upright shaft 25 at a consiralbly ,lower. rate of speedthan that of theshaft -29- for a purpose presently described. I I

A horizontal bearmg member or head ---32- having an offset upright hub -33- is supported upon the upper end of the bearing 24. of the bracket 23 and also upon the upper end of the shaft 25 so as to extend partially across the face of the rotary grinder 18 and is adjustable angularly about the axis of the upright shaft 25 to different angles relatively to the axis of the grinder --18- as may be required to grind the valves to different angles.

This horizontal bearing --32 is adapted to receive and support a rotary work holder 35- which comprises a sleeve 36- and a collet chuck -37 the latter being adapted to receive and support the work such, for ex.-

ample, as the stem aof a poppet valve The sleeve 36 is journaled in the bearing '32 tangential to the shaft 25 for relative rotation therein in said bearing and is provided intermediate its ends with a worm gear 38 formed by cutting the teeth in the periphery of the sleeve and adapted to mesh with a gear worm 3.9 on the upper end of the upright shaft -25, Figure 2.

The chuck 37 preferably consists of atube split longitudinally through portions of its length from both ends and having each "end tapered for engaging similarly tapered end thrust bearings and i0 atcorresponding ends of the chuck the tapered bearing 40 being preferably formed on the adjacent end of the sleeve 36 while the other tapered bearing -40 is movable axially within the sleeve and is adapted to be tightened and released for clamping and releasing the work by means of an adjusting screw -41 in the adjacent end of the sleeve. l

The axially adjustable bearing 40' and screw '4l are provided with registering openings C o-axial with the axis of the tubular chuck 35 to permit the stem of the valve to extend thereinto when the head of a the valve at the opposite end of the bearing 32- is in position for grinding.

WVhen it is desired to clamp the stem of the valve in the chuck -35 the screw 41 will be turned to force the movable bearing the grinding operation.

Reversing the direction of rotation of the screw 41 willvrelease the conical bearing -40 and thereby permit the jaws of the chuck 35- to open for releasing the valve stem and permitting the valve to be withdrawn after ithas been properly ground.

The head of the screw i1 is provided with an annular groove 42 for receiving the peripheral portion of the head 43 of a stop screw"44 which is adjustable in a threaded boss 45 on the under side of the bearing 32 and is frictionally held in its adjusted position by a friction screw 46 in one side of the lug 45, Fig. 2.

The object of engaging the head i3 of the stop screw 44 in the grooved head of the screw -41 is to prevent accidental turning of said screw during the rotation of the work holder with the work therein particularly when the latter is engaged with the rotary grinder l8.

The work holder is arranged in such manner as to support the part of the work to be ground, as, for example, the valve a-- in contact with the outer end face of the rotary grinder -18 in approximately the horizontal plane of the axis of said grinder so that when the grinder is rotated at a relatively high rate of speed the valve or other work held in the chuck 35-- will be rotated at a relatively low rate of speed so as to produce a smooth finish on the work during one revolution of the work holder and at the same time reducing the liability of vibration of the work in the holder.

The angle of the seating faces of different valves varies and it, therefore, becomes necessary to adjust the bearing 32 and work holder therein to different angles relatively tothe axis of the grinder or rather relatively to the outer end face of the grinder, the angles of the valves being known and in order that the operator may set the work holder at the desired angle the periphery of the base of the upright hub 33 of the bearing 32 is graduated circumferentially at 4.-7 to register with a fixed mark 47 on the adjacent upper end of the hub 24, Figure 3.

Operation The driving shaft -11 is adapted to be rotated by hand clockwise at any suitable speed for rotating thegrinder in a reverse direction at a considerably higher rate of speed through the medium of the relatively large gear 11.

This rotation of the gear 14. will impart a rotary motion to the shaft 29, Figure 2, through the medium of the pinion 30 meshing therewith, which rotary motion will be again transmitted to the upright shaft 25-, Figure 2, through the medium of the worm 31 and gear 28 and thence through the worm 39 and gear 38 to the work holder 35- in which the work, such, for example, as the valve a, is held and rotated against the outer end face of the grindstone.

The angle of contact of the work in the holder 35 relatively to the grinding face of the grinder 18 may be changed at will by simply adjusting the bearing 32 about the axis of the shaft 25.

The hand screw 41 and stop screw -44;- are conveniently available for adjustment and permit the double cone split collet 37- to be easily and quickly adjusted axially for tightening and releasing the work therein and therefrom, the cones at the ends of the collet being spaced some distance apart which, together with the factthat the collet is split inwardly from both ends beyond each other, permits the collet to be sprung into and out of engagement with the stem of the valve or other work throughout the length of the collet for firmly holding the stem against lateral springing or vibration during the grinding operation and thereby assuring a smooth and uniform grinding of the face of the valve.

What I claim is:

l. A work holder for rotary abrasive grinders comprising a rotary driving shaft, a retary driven shaft tangential to the driving shaft and geared directly thereto to receive motion therefrom, a rotary sleeve tangential to the driven shaft and geared directly thereto to be rotated thereby, a chuck mounted within the sleeve to rotate therewith for receiving and engaging the work, and means for tigntening and releasing the chuck upon and from the work.

2. A work holder for rotary abrasive grinders comprising a shaft, means for rotating the shaft, a rotary sleeve extending tangentially across one side of the shaft and geared directly thereto to receive motion therefrom, a chuck mounted within the sleeve to rotate therewith, and means for tightening and releasing the chuck upon and from the work.

A. work holder for rotary abrasive grinders comprising a shaft, means for rotating the shaft, a rotary sleeve extending tangentially across one side of the shaft and geared directly thereto to receive motion therefrom, a chuck mounted within the sleeve to rotate therewith, means for tightening and releasing the chuck upon and from the work, and means for supporting the sleeve for angular movement about the axis of the shaft.

l. A work holder for rotary abrasive grinders comprising a rotary driving shaft, a rotary driven shaft tangential to the driving shaft and geared directly thereto to receive motion therefrom, a rotary sleeve tangential to the driven shaft and geared directly thereto to be rotated thereby, a chuck mounted within the sleeve to rotate therewith for re ceiving and engaging the work, means for tightening and releasing the chuck upon and from the work, and means for supporting the driven shaft for angular adjustment about the axis of the driving shaft.

A work holder for rotary abrasive grinders comprising a rotary driving shaft, a rotary driven shaft tangential to the driving shaft and geared directly thereto to receive motion therefrom, a rotary sleeve tangential to the driven shaft and geared directly thereto to be rotated thereby, a chuck mounted within the sleeve to rotate therewith for receiving and engaging the work, means for tightening and releasing the chuck upon and from the work, means for supporting the driven shaft for angular adjustment about the axis of the driving shaft, and means for supporting the sleeve for angular adjustment about the axis of the driven shaft.

6. In a grinding machine having a gear case and a rotary shaft j ournaled therein and provided with a pinion, in combination with a bracket mounted on the gear case and adjustable angularly about the axis of said shaft, means for clamping the bracket in. its adjusted position, an additional shaft journaled in the bracket and provided with a gear meshing with said pinion, a head mounted on the bracket and adjustable angularly about the axis of the additional shaft, a sleeve rotatably mounted in said head at one side of the additional shaft and geared directly thereto to receive motion therefrom, a chuck mounted within the sleeve to rotate therewith and means on the sleeve for tightening the chuck upon the work.

In witness whereof I have hereunto set my hand this 5th day of May, 1926.

JAMES HENRY LITTLER. 

